The modern practice of sedation is the end result of a process of evolution in alteration of consciousness, likely starting with the discovery of the analgesic properties of ether. Recent technological advances have drastically changed the practice of sedation. One of the most significant was certainly the development of pulse oximetry during World War II by Glen Millikan. In 2002, the American Society of Anesthesiologists (ASA) appointed a task force to update practice guidelines for non-anesthesiologists administering sedation and analgesia. The Association of periOperative Registered Nurses (AORN) has produced guidelines for what every registered nurse should know about "conscious sedation". According to the AORN, moderate sedation/analgesia is produced by the administration of amnesic, analgesic, and sedative pharmacologic agents. With continued attention to a high standard of safety, many different professionals are able to provide sedation services to those patients who need them.